The problem of technical condition identification of aging oil pipelines in Russian Federation and in the world is relevant, since a significant number of them have been in service for over 30 years. More and more of them are getting closer to running out of normative resources. Within a method for reducing the size of task of identifying the technical condition of oil pipelines there were created special types of multigraph models (MGM) with interval-valued states of geometric characteristic of metallic shell defects.
Depending on oil pipelines operation time, the behavior of proposed models has been examined and operating performance with due account for technical condition identification has been determined, also the possibility of diminishing scope of inspections and repair works was shown. Multigraph models proposed here contain a set of states, which were singled out for the first time according to the analogue variable and are connected with multidirectional arcs with intensities of damage calculated on the relative amount of defects in the states.